diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2013-10-31 17:41:23 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-11-06 12:34:23 +0100 |
| commit | 394570b7939e1262f39373866166d8ee0a506e88 (patch) | |
| tree | 788cce8f829319e3b08d5851c469f6b9a7a5ef41 /kernel/events/ring_buffer.c | |
| parent | perf: Optimize perf_output_begin() -- address calculation (diff) | |
| download | linux-394570b7939e1262f39373866166d8ee0a506e88.tar.xz linux-394570b7939e1262f39373866166d8ee0a506e88.zip | |
perf: Update a stale comment
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: james.hogan@imgtec.com
Cc: Vince Weaver <vince@deater.net>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Anton Blanchard <anton@samba.org>
Link: http://lkml.kernel.org/n/tip-9s5mze78gmlz19agt39i8rii@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/events/ring_buffer.c')
| -rw-r--r-- | kernel/events/ring_buffer.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index c52a32fa5592..e8b168af135b 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -85,8 +85,8 @@ again: rb->user_page->data_head = head; /* - * Now check if we missed an update, rely on the (compiler) - * barrier in atomic_dec_and_test() to re-read rb->head. + * Now check if we missed an update -- rely on previous implied + * compiler barriers to force a re-read. */ if (unlikely(head != local_read(&rb->head))) { local_inc(&rb->nest); |